Ball caster



Oct. 5, 1954 FREDDOLINO BALL CASTER Filed June 50, 1953 HHII ' INVENTOR.

Patented Oct. 5, 1954 UNITED STATES PATENT. OFFICE BALL CASTER Louis Freddolino, Bronx, N. Y.

Application June 30, 1953, Serial No. 365,089

3 Claims.

This invention relates to casters, and the main object is the provision of a novel and improved roller or ball caster which is eflicient and effective in operation and at the same time simple and inexpensive in cost of manufacture.

This caster is adapted to be secured or attached on the undersides or bottoms of legs of any articles, whether of furniture or other articles adapted to be moved or pushed or pulled from one place to another.

The above broad as well as additional and more specific objects will be clarified in the following description, wherein characters of reference refer to like-numbered parts in the accompanying drawing. It is to be noted that the drawing is intended solely for the purpose of illustration and that it is therefore neither desired nor intended to limit the invention necessarily to any or all of the exact details shown or described except insofar as they may be deemed essential to the invention.

Referring briefly to the drawing, Fig. 1 is a cross-sectional elevational view of the caster of this invention, taken on the line Il of Fig. 2.

Fig. 2 is a top plan view of the caster.

Fig. 3 is an elevational view of the same.

Referring in detail to the drawing, the numerals I and 2 indicate, respectively, the upper and the lower members of pieces constituting the two piece frame of the caster, within or between which a large central ball 3 is retained on or between rings, that is upper and lower rings, of balls 4 and 4a, the latter being relatively small.

The upper frame member I comprises a cylindrical housing 6 having a horizontal roof I integral therewith and having an internal circumferential groove or raceway 8 in the lower circumferential edge thereof in which small balls 4 ride.

Integral with and extending outward from the upper edge of the cylindrical housing 9, is an annular flange 5 having spaced holes 5a therethrough receptive of screws or the like for attaching the caster to the article of furniture or other article. Between the circumferential wall of the cylinder 6 and the flange 5, a plurality of spaced slots (four such slots are shown in the drawing) 6a are provided through the flange 5. It is to be noted that the thickness of the roof I of the cylinder 6 is one-half the thickness of the flange 5.

The lower frame member 2 comprises an elongated cylinder 9 of substantially the same thickness as that of the roof I and is provided with a number of upstanding (prior to assembly) fingers l0 which pass upward through the slots 6a and are, during assembly, bent inwards flush against the roof I, as shown in Fig. 1. Thus, in the completed caster the upper surfaces thereof all lie in a common horizontal level, which is desirable for stability of the attached caster.

The lower edge of the cylinder 9 has an internal flange ll of the same vertical thickness as the cylinder 6, and the flange II has an internal circumferential raceway l2 in its lower edge, similar to the raceway 8, and receptive of similar small balls 4a.

The large ball 3, which has a diameter considerably greater than that of the small balls 4 and 4a, substantially as illustrated in the drawing, is freely positioned between the rings of balls 4 and 4a, and the lowermost point of the surface of the ball 3 lies in the same horizontal plane as the lowermost points in the surfaces of the balls 4a. Thus, the large ball 3 and the small balls 4a are all in contact with the floor or ground surface.

It is apparent that, with the weight of the supported article thus distributed to the floor through the large ball 3 and the small balls 4a, and with all of the balls 3, A and 4a free to rotate universally, a roller movement along the floor is obtained with a minimum of frictional resistance.

Moreover, with the simplicity of the two-piece frame structure set forth, assembly of the caster is an extremely simple and inexpensive matter. A caster constructed along the lines of this invention will serve a long and efficient life.

Obviously, modifications in form or structure may be made without departing from the spirit or scope of the invention.

I claim:

1. A caster comprising a two-piece frame including an upper frame piece and a lower frame piece, said upper piece comprising a relatively short and relatively thick vertical cylinder having an internal raceway in the lower circumfertial edge thereof, said cylinder having a roof integral therewith and having a horizontal flange extending therefrom, the lower surfaces of said roof and said flange lying in a common plane, said flange having spaced holes therethrough receptive of screws or the like for attaching the caster to an article adapted to ride on a surface, said lower piece comprising an elongated vertical tubular cylinder having an internal diameter substantially equal to the external diameter of said short cylinder and having said short cylinder registering in the top thereof, said elongated cylinder having an internal flange on the lower edge thereof of substantially the same thickness as said short cylinder, said internal flange having an internal raceway in the lower circumferential edge thereof, each of said raceways having a plurality of relatively small balls mounted therein, a relatively much larger ball mounted within the frame between and in contact with the balls of said raceways, the lowermost point of said larger ball and the lowermost points of said small balls in said last-named raceway protruding from the bottom of the frame and lying in a common horizontal plane, and means for securing said upper piece and said lower piece together.

2. The caster set forth in claim 1, said means comprising circumferentially spaced fingers extending upwardly from said elongated cylinder prior to assembly of said frame, said horizontal flange of said upper piece having similarly circumferentially spaced slots therethrough adjacent said short cylinder, said fingers extending through said slots and being doubled back inwardly upon said roof.

3. The caster set forth in claim 1, said means comprising circumferentially spaced fingers extending upwardly from said elongated cylinder prior to assembly of said frame, said fingers having the same thickness as said elongated cylinder and hence having one-half the thickness of said horizontal flange, said horizontal flange having similarly circumferentially spaced slots therethrough adjacent said short cylinder, said fingers passing through said slots and being doubled back inwardly upon said roof, the upper surfaces of said doubled back fingers lyin in the same plane as the upper surface of said horizontal flange.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 604,400 Klose May 24, 1898 908,188 Woodward et al. Dec. 29, 1908 970,386 Nickerson Sept. 13, 1910 FOREIGN PATENTS Number Country Date 23,704 Great Britain of 1904 

